Thinopyrum intermedium
Encyclopedia
Thinopyrum intermedium (intermediate wheatgrass) is a sod
-forming perennial grass
. It is part of a group of plants commonly called wheatgrass because of the similarity of their seed heads or 'ears' to common wheat. However the wheatgrasses in general are perennial, while wheat is an annual.
Wild triga is the common name that was given to Thinopyrum intermedium by researchers at The Rodale Institute
. The name was intended to distinguish varieties of the species developed for use as a perennial grain crop from forage
cultivar
s which are identified by the common name "intermediate wheatgrass."
Many scientific binomial names have been given to the species Thinopyrum intermedium. Multiple species or subspecies have been described based on different morphologies, like the presence or absence of pubescence. Here is a partial list of the binomial synonyms for Thinopyrum intermedium:
Agropyron aucheri
Agropyron ciliatiflorum
Agropyron gentryi
Agropyron glaucum
Agropyron intermedium
Agropyron podperae
Agropyron pulcherrimum
Agropyron trichophorum
Elymus hispidus
Elytrigia intermedia
to Asia Minor
. Although it was first brought to the United States in 1907, the first successful introduction to that country was from in the Caucasus
region in 1932. The plant can now be found growing wild throughout the western half of the United States and Canada. It is best adapated to:
. This species is among the most productive forage species for the western United States. Because it heads relatively late, it can be grown effectively in mixture with alfalfa
to increase its productivity, longevity, and forage quality. It regrows slowly after grazing or cutting, making it best suited to management with a single harvest per year. If multiple harvests are needed per year, other species will be more produtive. If managed well, stands can persist for up to 50 years.
Habitat
for wildlife
. Intermediate wheatgrass can be an excellent food source for grazing
and browsing
animals. Left unharvested, the vegetation is good nesting habitat for some birds and waterfowl
. Generally, it is not an invasive plant, and coexists well with native plant species.
Erosion control
and land rehabilitation
. It establishes quickly to form a protective mat of roots
and rhizomes, even when planted on soils degraded by earth moving or mining
. Within five years, stands have produced up to 7000 pounds of dry root mass per acre in the top 8 inches of soil.
Heavy root production holds the soil in place and restores its natural fertility by increasing the soil carbon
.
Perennial grain
. In 1983, the Rodale Research Center evaluated close to 100 species of perennial grasses to identify those with good potential for development into perennial grain crops. Intermediate wheatgrass was selected as the most promising species based on: flavor, ease of thresing, large seed size, resistance to shattering, lodging
resistance, ease of harvest, and perennial growth. Intermediate wheatgrass is nutritionally similar to wheat, and the grain can be ground into flour and used for food products, including muffins, tortillas, pancakes, cookies, crackers, and breads.
, seed production is essential because farmers and ranchers continue to establish new stands by planting seed. In 1988 over 500 metric tons of seed were harvested in Saskatchewan
alone, although more recently the harvest has fallen to less than 225 metric tons in that Canadian province. Average seed yields are about 330 pounds per acre, but on-farm yields of up to 880 pounds per acre have been achieved. Seed is generally produced in rows spaced 30 to 36 inches apart. The wide row spacing (relative to grain crops like wheat
) allows for sustained seed yields for five to ten years. Without spacing and occasional tillage
between the rows, yields decline rapidly as the plant population becomes increasingly dense through rhizome
spread.
In 2001 and 2002, seed from the first and second breeding cycles of the Rodale Research Center was planted at The Land Institute. In the fall of 2003, 1000 individuals were dug up and vegetatively propagated to obtain three clones of each plant. The 3000 resulting plants were randomly transplanted to the field on a three foot by three foot grid. In this manner, genetic differences between plants were separated from the environmental influences. In 2005, heads were harvested from every plant and threshed to remove the seeds. The seeds were both counted and weighed to determine the yield per seed head and weight per seed. The fifty highest plants with the highest yield and largest seed were selected to intermate in 2004.
In the fall of 2004, 4000 progeny were planted to establish the second cycle of breeding at The Land Institute. In 2008, these plants were harvested separately by using a power sythe and threshed in a combine. Again the best 50 plants were selected, this time based on yield per head, seed size, shortness, and free threshing ability.
The selection methods described above have increased seed size and yield by about 10 to 18% per cycle. But perhaps of greater importance has been the discovery of two Mendelian traits. The first is dwarfing, which results in stems about 30 cm shorter than wild type plants and short, erect leaves (see photo). The second is a more subtle change in head shape which results in thick, non-brittle heads and slightly larger seeds (see photo). Both of these traits appear to be controlled by dominant genes.
Sod
Sod or turf is grass and the part of the soil beneath it held together by the roots, or a piece of thin material.The term sod may be used to mean turf grown and cut specifically for the establishment of lawns...
-forming perennial grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
. It is part of a group of plants commonly called wheatgrass because of the similarity of their seed heads or 'ears' to common wheat. However the wheatgrasses in general are perennial, while wheat is an annual.
Synonyms
Intermediate wheatgrass is the most widely used common name for Thinopyrum intermedium in the United States. The name "intermediate" probably refers to the height of the plant, which is generally somewhat shorter than Thinopyrum ponticum, known by the common name of "tall wheatgrass."Wild triga is the common name that was given to Thinopyrum intermedium by researchers at The Rodale Institute
The Rodale Institute
The Rodale Institute was founded in 1947 by J. I. Rodale as the Soil and Health Foundation. It continues as a working organic crop farm with research trials and a visitor’s center near Kutztown, Pennsylvania....
. The name was intended to distinguish varieties of the species developed for use as a perennial grain crop from forage
Forage
Forage is plant material eaten by grazing livestock.Historically the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially...
cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s which are identified by the common name "intermediate wheatgrass."
Many scientific binomial names have been given to the species Thinopyrum intermedium. Multiple species or subspecies have been described based on different morphologies, like the presence or absence of pubescence. Here is a partial list of the binomial synonyms for Thinopyrum intermedium:
Agropyron aucheri
Agropyron ciliatiflorum
Agropyron gentryi
Agropyron glaucum
Agropyron intermedium
Agropyron podperae
Agropyron pulcherrimum
Agropyron trichophorum
Elymus hispidus
Elytrigia intermedia
Origin and Distribution
The native range of intermediate wheatgrass extends from central and southeastern EuropeEurope
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
to Asia Minor
Asia Minor
Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...
. Although it was first brought to the United States in 1907, the first successful introduction to that country was from in the Caucasus
Caucasus
The Caucasus, also Caucas or Caucasia , is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea...
region in 1932. The plant can now be found growing wild throughout the western half of the United States and Canada. It is best adapated to:
- Regions with annual rainfall between 12 and 30 inches
- Soil with a pHPHIn chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
between 5.6 and 8.4 - Locations with full exposure to sun
- A wide range of soilSoilSoil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
s but with minimum depth of 16 inches - Locations where the minimum temperature exceeds -38°F
Uses
ForageForage
Forage is plant material eaten by grazing livestock.Historically the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially...
. This species is among the most productive forage species for the western United States. Because it heads relatively late, it can be grown effectively in mixture with alfalfa
Alfalfa
Alfalfa is a flowering plant in the pea family Fabaceae cultivated as an important forage crop in the US, Canada, Argentina, France, Australia, the Middle East, South Africa, and many other countries. It is known as lucerne in the UK, France, Australia, South Africa and New Zealand, and known as...
to increase its productivity, longevity, and forage quality. It regrows slowly after grazing or cutting, making it best suited to management with a single harvest per year. If multiple harvests are needed per year, other species will be more produtive. If managed well, stands can persist for up to 50 years.
Habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
for wildlife
Wildlife
Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....
. Intermediate wheatgrass can be an excellent food source for grazing
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...
and browsing
Browsing (predation)
Browsing is a type of herbivory in which an herbivore feeds on leaves, soft shoots, or fruits of high growing, generally woody, plants such as shrubs. This is contrasted with grazing, usually associated with animals feeding on grass or other low vegetation...
animals. Left unharvested, the vegetation is good nesting habitat for some birds and waterfowl
Waterfowl
Waterfowl are certain wildfowl of the order Anseriformes, especially members of the family Anatidae, which includes ducks, geese, and swans....
. Generally, it is not an invasive plant, and coexists well with native plant species.
Erosion control
Erosion control
Erosion control is the practice of preventing or controlling wind or water erosion in agriculture, land development and construction. Effective erosion controls are important techniques in preventing water pollution and soil loss.-Introduction:...
and land rehabilitation
Land rehabilitation
Land rehabilitation is the process of returning the land in a given area to some degree of its former state, after some process has resulted in its damage...
. It establishes quickly to form a protective mat of roots
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
and rhizomes, even when planted on soils degraded by earth moving or mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
. Within five years, stands have produced up to 7000 pounds of dry root mass per acre in the top 8 inches of soil.
Heavy root production holds the soil in place and restores its natural fertility by increasing the soil carbon
Soil carbon
Soil carbon is the generic name for carbon held within the soil, primarily in association with its organic content. Soil carbon is the largest terrestrial pool of carbon. Humans have, and will likely continue to have, significant impacts on the size of this pool...
.
Perennial grain
Perennial grain
While many fruit, nut and forage crops are long-lived perennial plants, all major grain crops are annuals or short-lived perennials grown as annuals. Scientists from several nations have argued that perennial versions of today's grain crops could be developed and that these perennial grains could...
. In 1983, the Rodale Research Center evaluated close to 100 species of perennial grasses to identify those with good potential for development into perennial grain crops. Intermediate wheatgrass was selected as the most promising species based on: flavor, ease of thresing, large seed size, resistance to shattering, lodging
Lodging
Lodging is a type of residential accommodation. People who travel and stay away from home for more than a day need lodging for sleep, rest, safety, shelter from cold temperatures or rain, storage of luggage and access to common household functions.Lodgings may be self catering in which case no...
resistance, ease of harvest, and perennial growth. Intermediate wheatgrass is nutritionally similar to wheat, and the grain can be ground into flour and used for food products, including muffins, tortillas, pancakes, cookies, crackers, and breads.
Seed Production
Although the primary use of this species is as a forageForage
Forage is plant material eaten by grazing livestock.Historically the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially...
, seed production is essential because farmers and ranchers continue to establish new stands by planting seed. In 1988 over 500 metric tons of seed were harvested in Saskatchewan
Saskatchewan
Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....
alone, although more recently the harvest has fallen to less than 225 metric tons in that Canadian province. Average seed yields are about 330 pounds per acre, but on-farm yields of up to 880 pounds per acre have been achieved. Seed is generally produced in rows spaced 30 to 36 inches apart. The wide row spacing (relative to grain crops like wheat
Wheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
) allows for sustained seed yields for five to ten years. Without spacing and occasional tillage
Tillage
Tillage is the agricultural preparation of the soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shovelling, picking, mattock work, hoeing, and raking...
between the rows, yields decline rapidly as the plant population becomes increasingly dense through rhizome
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...
spread.
Breeding for Grain Production
Intermediate wheatgrass has been widely hybridized with wheat in efforts to transfer traits like disease resistance or perenniality to wheat. But attempts to directly domesticate the species as a grain crop did not begin until workers at the Rodale Research Center began to evaluate collections in 1983. After evaluating 300 collections, the best 20 based on grain yield and seed quality were selected in 1989. The selected collections were allowed to intermate, and 380 progeny were evaluated between 1991 and 1994. The best 11 plants, plus three from another evaluation, were interemated, and a second cycle was begun. Seeds from the best plants in the second cycle were passed to scientists at The Land Institute, where the research has continued.In 2001 and 2002, seed from the first and second breeding cycles of the Rodale Research Center was planted at The Land Institute. In the fall of 2003, 1000 individuals were dug up and vegetatively propagated to obtain three clones of each plant. The 3000 resulting plants were randomly transplanted to the field on a three foot by three foot grid. In this manner, genetic differences between plants were separated from the environmental influences. In 2005, heads were harvested from every plant and threshed to remove the seeds. The seeds were both counted and weighed to determine the yield per seed head and weight per seed. The fifty highest plants with the highest yield and largest seed were selected to intermate in 2004.
In the fall of 2004, 4000 progeny were planted to establish the second cycle of breeding at The Land Institute. In 2008, these plants were harvested separately by using a power sythe and threshed in a combine. Again the best 50 plants were selected, this time based on yield per head, seed size, shortness, and free threshing ability.
The selection methods described above have increased seed size and yield by about 10 to 18% per cycle. But perhaps of greater importance has been the discovery of two Mendelian traits. The first is dwarfing, which results in stems about 30 cm shorter than wild type plants and short, erect leaves (see photo). The second is a more subtle change in head shape which results in thick, non-brittle heads and slightly larger seeds (see photo). Both of these traits appear to be controlled by dominant genes.